Debt (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Total debt, including the current portion of long-term debt
Long-term debt, gross	$ 1,003.8	$ 640.0
Original issue premium	12.1	11.5
Debt issuance costs	(17.1)	(18.0)
Total debt	998.8	633.5
Current portion of long-term debt	1.1	0.0
Total long-term debt	997.7	633.5
7.625% senior notes, due 2019 \| Senior Notes
Total debt, including the current portion of long-term debt
Long-term debt, gross	44.6	240.0
SunCoke Revolving Credit Facility, due 2018 \| Line of Credit \| Revolving credit facility
Total debt, including the current portion of long-term debt
Long-term debt, gross	60.4	0.0
7.375% Partnership notes, due 2020 \| Senior Notes
Total debt, including the current portion of long-term debt
Long-term debt, gross	552.5	400.0
Promissory notes, due 2021 \| Senior Notes
Total debt, including the current portion of long-term debt
Long-term debt, gross	114.3	0.0
Partnership revolver, due 2019 \| Line of Credit \| Revolving credit facility
Total debt, including the current portion of long-term debt
Long-term debt, gross	182.0	0.0
Partnership Term Loan Due 2019 \| Line of Credit
Total debt, including the current portion of long-term debt
Long-term debt, gross	$ 50.0	$ 0.0

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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